Cam and follower tests.

Bruce MacGregor said:

Hi, Since we have some very talented people here. Has any one considered developing a Roller Cam and Cam shaft for our Norton engines ?

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A successful roller lifter would solve the problem - if everything worked.

Another version.


Expensive - more expensive than making a lighter thin walled steel lifter that would braze well to the pad. Either way it would take someone crazy enough to take the risk of failure - especially when there are other proven solutions. Designing the cam would not be the problem. The lifters would be the problem. Look at Westlake speedway motor roller lifters for a clue. Also dig up some Harmon & Collins roller lifters that were developed for Triumphs in the 1970s - good luck finding them.

knut

comparing QA small scale manufacture with Ferrari is very naive the Ferrari budget and resources will be cutting edge
the guy doing the QA at Ferrari will most likely be on an annual salary greater than ANDOVERS annual turnover

As for ISO9000 extended QA testing procedures by manufacturer from my own experiance most small UK producers would think ISO9000 QA is a new energy drink

as comnoz rightly pointed out the follower manufacturer has been subject to take overs and moved premissis
i guess like most of these small specialist companys has also had staff retire or leave so much of the knowledge
will have left the business and production standards will have slipped as a result

Small is debatable ? the figures you quote 300-500 followers and 100-200 cams ? i would anticipate much smaller batches based on the unit retail price alone it would not make sense to
invest so much in two product lines with limited sales and competition in the market

if i were Andover and could not get consistent production quality i would just stop selling followers , i did note they currently have no stock ( a wise decision me thinks )

I am just waiting for the final results , about what fitting in the next future, as I am not an expert !!
I am riding those cdo since 1974, without any problems, though I am riding less than before , the first one in 1974 got 30000 miles in a year , now I have three bikes with BSA lifters , and four with std flats ones , using most of the time cheap GTX castrol, or local French SG rated multi...

Frankie17 said:

comparing QA small scale manufacture with Ferrari is very naive the Ferrari budget and resources will be cutting edge
the guy doing the QA at Ferrari will most likely be on an annual salary greater than ANDOVERS annual turnover

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This is a rubbish argument - so typical british to reject an idea or a objective by making invalid comparisons.
The top QA boss at Ferrari probably has an earning in the 100-125K Euro range, and common QA staff will be technicians with a salary in the range of 25K Euro.
Compare this to the estimated turnover of A-N of 2.5 M£ (about 3.0M €). Staffing at A-N is 8-9 full time emplyees, as per the latest pictures. The average salery will be in the 25K£ range (30K €).
I read this comment on a Ferrari BB: "I live here and the salary in Ferrari is BELOW the average salary in the other company in this area."
Testing equipment cost about the same in Italy as it does in the UK. Only a few items needs to be measured on a high-end CMM worth £1 mill or checked in a 3D X-ray machine, you know.
Ferrari produces 5000 cars a year, and for this low output, it's still cheaper to use humans for QA than invest in automated testing equipment.
So - why shouldn't A-N be in a position to perform basic QA testing similar to what Ferrari does? Of course they are. A-N already holds most of the testing equipment used at N-V according to their home page.

Frankie17 said:

As for ISO9000 extended QA testing procedures by manufacturer, from my own experiance most small UK producers would think ISO9000 QA is a new energy drink

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Hahaha ... I sincerely hope A-N is not dealing with these companies, at least not for engine and transmission parts. There should be sufficiently many companies the size of Newman Cams who run a professional operation and monitor quality according to ISO9000 as endorsed by BSI.

Frankie17 said:

as comnoz rightly pointed out the follower manufacturer has been subject to take overs and moved premissis
i guess like most of these small specialist companys has also had staff retire or leave so much of the knowledge
will have left the business and production standards will have slipped as a result

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That may be, but is of no relevance. It doesn't make business sense to hold on to a supplier for historical reasons. A-N should have taken steps to restore quality the moment they observed quality slipping - maybe they have now. Hopefully A-N will find a professional replacement to resume supply of tappets.

-Knut

marinatlas said:

I am just waiting for the final results , about what fitting in the next future, as I am not an expert !!
I am riding those cdo since 1974, without any problems, though I am riding less than before , the first one in 1974 got 30000 miles in a year , now I have three bikes with BSA lifters , and four with std flats ones , using most of the time cheap GTX castrol, or local French SG rated multi...

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Hi M-Atlas, watch out for the ZDDP content! It should be at 1200 ppm or above.
From a technical point of view, how many miles have you put on the bikes fitted with BSA lifters, alltogether?

-Knut

Norton follower bodies are made of semi-steel. Semi-steel is a worthless term referring to a grade of metal with less graphite than g2 cast but more than steel. Similar to many lathe chucks.

Furnace brazing is not an issue if done correctly. No different than BSA lifters which are low carbon steel.

Semi-steel was used because it was compatible with the metal of the barrel. [you do not generally want two parts of similar material and hardness in sliding contact] and because it is rigid. Jim

Having worked in industry in both the UK and Italy! I am a bit frustrated with the ignorance creeping in here.

ISO 9000 does not define any of the procedures you should perform in QA testing! You do, and you compile processes/procedures in your ISO 9000 Quality Manual. Your processes are then reviewed, but more importantly when the manual is approved you record your activities as completed, they must be in line with your approved QA manual. That is how it works.

I would be surprised to see the head of QA at Ferrari paid 100 to 125K€, considering the equivalent pay in Northern Italian Aerospace companies, but I can agree that the guys doing the job will be paid around 25K€, departmental manager maybe up to 40K€, but be aware that Italian industrial workers are paid a salary defined by the government, not the company. The pay rate is for the grade of employee, it is nationwide, companies only have a little flexibility in how they grade each job.

AN themselves have recently stated that there are issues with follower manufacture based on the cost to do the work, particularly the external round grind of the cast section, due to it being time consuming. I believe this relates to the dimension issues rather than failure issues, having to hand fettle them for you cylinder barrel. This is a pain for an installer like me, but once done it is done and you would not expect this issue to lead to a failure. My assumption is that things like pad material hardness are separate from this issue. But that hardness does have a bearing on service life.

We may also be looking at a hardness issue that goes back longer than we think, but has only affected a percentage of production!

Here was the main problem that caused the separation of the pad from the body of the follower on the older followers. Simply sloppy fitting or brazing.

The BSA follower that I used that broke in my motor was also fitted on poorly although it was not as evident as this one. One half of the Stellite pad was poorly supported because there was a void in the weld. That half broke off. The sharp edge that resulted dug into the cam immediately.

You can see how the pad is not evenly fitted to the body. It is likely that this follower would have come apart sooner or later.

This follower also tested at RHc58 .

mdt-son said:

Hi M-Atlas, watch out for the ZDDP content! It should be at 1200 ppm or above.
From a technical point of view, how many miles have you put on the bikes fitted with BSA lifters, alltogether?

-Knut

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You are right in the fact that the BSA lifters bikes are not used so many (one is a Seeley , sitting in the shed waiting for better days , next one is an Atlas wit Cdo engine and those lifters were the one supplied by Les in the 90's, the next one is a spare engine with lifters from Yves the big spender owner's), the problem when you are getting old and you have too much bikes is that you ride them less just because you are older than before , when you had only one and no car ...........!!!!!!!!
The Redline is only for the Seeley , and next time I will uise Penrite enduro 20w70 which is rated SG and 1750 ppm of ZDDP, otherwise , I use TOTAL 20w50 rated SG /SF, which seems to be OK , but sincerly not clue about ZDDP......!

SteveA said:

Having worked in industry in both the UK and Italy! I am a bit frustrated with the ignorance creeping in here.

ISO 9000 does not define any of the procedures you should perform in QA testing! You do, and you compile processes/procedures in your ISO 9000 Quality Manual. Your processes are then reviewed, but more importantly when the manual is approved you record your activities as completed, they must be in line with your approved QA manual. That is how it works.

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A bit of a sidetrack now. Thank you for pointing out ISO 9000 is primarily a QMS (Quality Managment Standard) and that the specific manufacturing and testing processes have to be worked out by the actual business. However, the standard also describes in general terms product realization, including the steps from design to delivery; and measurement, analysis, and improvement of the QMS through activities like internal audits and corrective and preventive actions. The quality manual itself is part of the procedures undergoing continuous improvements.

For instance, if a flaw in the manufacture of tappets is detected, the quality manual would have to be revised to address this and "turn off" the flaw by an alternate process. Furthermore, specific testing and inspection steps would have to be specified to monitor the attainment of specific attributes, ensuring the flaw not to appear again. Improving the efficiency of processes and continually improving the manufacturing plant as an entity are some of the benefits in using ISO 9000.

-Knut

comnoz said:

Here was the main problem that caused the separation of the pad from the body of the follower on the older followers. Simply sloppy fitting or brazing.
The BSA follower that I used that broke in my motor was also fitted on poorly although it was not as evident as this one. <..>
You can see how the pad is not evenly fitted to the body. It is likely that this follower would have come apart sooner or later.

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Stellite (Co-Cr alloy) pads tend to have low ductility, which can cause component fracture if poorly supported by the follower body.

One manufacturing method to ensure perfect bonding of stellite and follower bodies is by explosion forming, by which atomic structures of each constituent wanders into each other, creating virtually a homogenous part. Separation of the stellite pad becomes impossible. No degradation of stellite occurs because no heat is involved. I don't know if this process works with lifter bodies made of high carbon steel as used here (probably in order to achieve high wear resistance), but it will work with follower bodies made of low carbon steel or maraging steels. In this process, several followers and pads may be bonded at the same time. The process was used frequently in the aerospace industry in the 60's and 70's.

-Knut

Explosion welding would likely be one alternative -or course it still relies on someone correctly carrying out the process.
Of course spiggoting the followers is also a good design and is capable of being done very successfully. I have several spiggotted followers here that test in the RHc63 range and are in perfect condition after use.
I also have a couple that test in the 40'S and have never been installed.

Good life from a cam and follower depends on a lot of things. Compatible metals and hardness of the parts is only one of them. Oil additives and film strength are also important, but any oil film or follower hardness is going to be compromised if the load between the cam and follower is too high.

Most people do not realize that the point of highest pressure contact between the cam and follower during operation is on the falling side of the lobe. Usually 30 to 40 cam degrees after peak lift at road speed.
If you look at many Norton cams and followers - particularly performance cams -you will see varying amounts of distress visible at this position -both on the cam and the follower.

This point of high pressure contact is influenced by the valve, cap and effective spring weight to an extent -but the largest contributor to this point of high pressure is the cam design -IE the rates of change of valve velocity ground into the cam or follower.

If the cam attempts to change the velocity of the valve too quickly then the inertia of the valve takes over for an instant and when the valve catches back up to the cam, the impact pressure can be rather severe. Many times higher than the pressure exerted by the valve spring alone.

This is why you often see the first signs of cam failure due to weak springs on the closing side of the lobe.

This is also why Lycoming who has had lots of cam problems has gone to great lengths with computer designed lobes to reduce the pressure spikes between the cam and follower. Reportedly this has been more successful than the conversions to roller followers that have been common with their engines.

I have also seen some good results using asymetrical valve action on the Norton motors but this still needs further testing. Jim

comnoz said:

Here was the main problem that caused the separation of the pad from the body of the follower on the older followers. Simply sloppy fitting or brazing.

The BSA follower that I used that broke in my motor was also fitted on poorly although it was not as evident as this one. One half of the Stellite pad was poorly supported because there was a void in the weld. That half broke off. The sharp edge that resulted dug into the cam immediately.

You can see how the pad is not evenly fitted to the body. It is likely that this follower would have come apart sooner or later.

This follower also tested at RHc58 .

View attachment 6151

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I think that I should do a liquid penitrent test on my lifters before I use them.
I wonder Jim if Easy.flo 45 would be a better choice in bonding the stellite pad.
The temperatures for melting would be lower and I think much stronger if done properly.
I am not sure how the originals are bonded.
But food for thought.
Cheers,
Thomas

Just for a look I took a bunch of old followers and put them in my mill vise. I cut a slot in a piece of hardened steel just wide enough to fit the Stellite pad. I found three that broke loose pretty easily and one that didn't.

The one on the right is the follower from above.

The follower on the left broke the body before the pad cam off.

CanukNortonNut said:

I think that I should do a liquid penitrent test on my lifters before I use them.
I wonder Jim if Easy.flo 45 would be a better choice in bonding the stellite pad.
The temperatures for melting would be lower and I think much stronger if done properly.
I am not sure how the originals are bonded.
But food for thought.
Cheers,
Thomas

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By the color I suspect the braze is a silver/bronze alloy.
The melting temp seems to be ~12 to 1300 F.

Jim,
Looks like some definitely are not bonded correctly. That is a major concern. In my apprenticeship years as a Millwright my Instructor taught us how to prep a part using easy.flo. Our test was two 3/8" key-stock pcs 4" long, joined end to end with this braze process. When finished we would bring it up to him and he would put one section in the vice and turn the other side 180 degrees with an adjustable wrench. Twisting the key-stock. If the joint failed he would hand it back to you and tell you to do it again. Mine passed by the way but I became quite impressed with this materials strength for brazing process.
Cheers,
T

comnoz said:

Just for a look I took a bunch of old followers and put them in my mill vise. I cut a slot in a piece of hardened steel just wide enough to fit the Stellite pad. I found three that broke loose pretty easily and one that didn't.

The one on the right is the follower from above.

The follower on the left broke the body before the pad cam off.

View attachment 6156

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Jim
Do you think NDT with dye penetrant, as Thomas suggested above, would be effective in finding the faulty/weak ones?
Rob

robs ss said:

Jim
Do you think NDT with dye penetrant, as Thomas suggested above, would be effective in finding the faulty/weak ones?
Rob

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Maybe only the worst ones. I would hate to count on it.

The photo below is typical of the followers from my 650SS they all "look" good to my eye. (excuse the engraving - Right-outer)
It would be nice to have an effective technique to prove integrity - maybe ultrasonics would pick up any air in the joint?

This is a rubbish argument - so typical british to reject an idea or a objective by making invalid comparisons.
The top QA boss at Ferrari probably has an earning in the 100-125K Euro range, and common QA staff will be technicians with a salary in the range of 25K Euro.
Compare this to the estimated turnover of A-N of 2.5 M£ (about 3.0M €). Staffing at A-N is 8-9 full time emplyees, as per the latest pictures. The average salery will be in the 25K£ range (30K €).
I read this comment on a Ferrari BB: "I live here and the salary in Ferrari is BELOW the average salary in the other company in this area."
Testing equipment cost about the same in Italy as it does in the UK. Only a few items needs to be measured on a high-end CMM worth £1 mill or checked in a 3D X-ray machine, you know.
Ferrari produces 5000 cars a year, and for this low output, it's still cheaper to use humans for QA than invest in automated testing equipment.
So - why shouldn't A-N be in a position to perform basic QA testing similar to what Ferrari does? Of course they are. A-N already holds most of the testing equipment used at N-V according to their home page.

Knut
you 2.5 M estimation of Andovers turnover ????? take a look at companies house as they are a LTD company

YOU WILL THEN SEE HOW VALID MY POINT IS REGARDING BATCH QUANTITYS AND QA if they do employ 9 staff at 25K / 30 k there is very little wiggle room based on accounts filed for the past few years , you will be shocked how small the so called big players really are

the classic motorcycle trade is a very small and niche business investment in the quality control process as you suggest is just out of reach of most traders
we will have to hope a real knowledgable guru such as Jim will invest his time and come up with a solution to this 40 year old problem i cannot see a commercial enterprise investing time and resources without a significant return on investment